This invention relates in general to the treatment of head lice, and in particular to a topical preparation and therapy for head lice.
Head lice is a persistent problem, especially among elementary school-aged children. It was reported that six million U.S. school children will become infested with head lice in one year, that is one out of every four students in elementary schools (Consumer Reports, February 1998). The total number of people in the U.S. infested with head lice in one year is about ten million when all ages are accounted for. The incidence of head lice is only slightly improved from the reported incidence in 1940, which was prior to the advent of insecticides and "superior" knowledge by the medical establishment.
Infestation with head lice typically causes itching of the scalp. In some cases, a person may develop lesions or papules on the scalp, swollen glands in the neck or under the arms, or other symptoms. A secondary problem is that many schools have forced absenteeism if a child has any nits (lice eggs) in their hair. Such a "no-nit" policy has negative social implications for the child and parents. Head lice is becoming a sensitive social issue.
Although head lice are not considered vectors for systemic human infection, the evidence strongly supports the possibility that head lice could be vectors. For example, rickettsiae and spirochetes are known to be obtainable from the blood of the host (head lice are blood suckers like mosquitoes); these organisms multiply in the gut of the head lice, and are also found in high numbers in their feces. Viruses, like the AIDS virus, also can be found in the gut and feces of head lice, but these organisms do not multiply in the gut of the louse; thus, the number of viruses in the feces would not be high. However, any organism in the blood of the host would be found in the feces of the louse, and thereby, could be potentially transmitted when the louse finds a new host, i.e., a new human being to infest.
Current commercial treatments for head lice include applying an insecticide on the scalp hair to kill the head lice. The pharmaceutically formulated insecticides are universally admixed in a water-based composition such as a shampoo, cream or lotion. Home remedies for head lice include applying petroleum jelly or mayonnaise on the scalp hair to smother the head lice. Unfortunately, these treatment methods have not been totally effective. Thus, it would be desirable to provide a topical preparation and a topical therapy in the treatment of head lice which are more effective than the current methods for treating head lice. With government restrictions on the available insecticides for treatment of head lice, unless a better delivery system is developed, the likelihood of resistance to insecticides will increase and more toxic insecticides may have to be used. This is especially true given the increased resistance that various cities are presently reporting. There is clearly a need for a safe, effective substitute for the present treatment regimens.